The Institute for Health Metrics and Evaluation (IHME) COVID-19 Forecasting team has advised that universal mask-wearing during the coronavirus disease 2019 (COVID-19) pandemic could save hundreds of thousands of lives and delay the need for mitigation measures such as stay-at-home policies.
Universal mask use would reduce the number of deaths that would have occurred between August 26th, 2020, and January 1st, 2021, by more than 815,000, says the team.
The reduced need for control measures would also help to lessen the adverse effects that COVID-19 is having on unemployment levels and the economy.
“The rising toll of the COVID-19 pandemic can be substantially reduced by the universal adoption of masks,” write the researchers. “This low-cost policy, whether customary or mandated, has enormous health benefits and likely large economic benefits as well, by delaying the need for re-imposition of social distancing mandates.”
A pre-print version of the paper is available in the server medRxiv*, while the article undergoes peer review.
Proportion of the population that self-report always wearing a facemask when outside the home on July 21, 2020.
Most nations have started to relax social distancing measures
Since the first cases of COVID-19 were first identified in Wuhan, China, late last year, the causative agent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has now infected more than 37.7 million people globally and has caused more than one million deaths.
In March 2020, nearly all nations implemented social distancing mandates to reduce transmission, but the subsequent economic downturns and increases in unemployment have led most nations to start relaxing these control measures.
With COVID-19 transmission and mortality rates now increasing in many low- and middle-income nations, as well as some high-income countries, policymakers are keen to find solutions to reducing the death rate, without re-introducing strict social distancing policies.
Percent reduction in cumulative deaths on January 1, 2021 in the universal mask use scenario and the reference scenario.
Reluctance to embrace mask use in some countries
One appealing option is requiring the wearing of facemasks in public spaces where social distancing is not feasible.
However, the World Health Organization (WHO) initially discouraged mask use and questioned the evidence supporting this practice and argued that it might lead to mask shortages for healthcare providers.
In countries such as the United States and Brazil, the use of masks has become a topic of political debate, with viewpoints on the ethics and legalities of enforcing the mandates varying widely.
“This reluctance to embrace mask use given no real risks of use and considerable potential health and economic benefits is hard to understand and justify,” said Emmanuela Gakidou and colleagues.
“Evidence of the individual benefits, population health impacts, and the potential economic benefits of increased mask use may be a useful input in these national debates,” they add.
What did the researchers do?
Now, Gakidou and colleagues have provided a meta-regression-based analysis of 40 studies assessing the effect of cloth or paper mask use on COVID-19 transmission and mortality in a general population setting and determined the current levels and trends in the use of the masks globally.
The team used daily data from Facebook, YouGov, and Premise surveys, on the proportion of people who reported always wearing a mask once outside their home, across nearly all countries.
“Global models of the impact of scaled-up mask use have to our knowledge not been published,” says the team.
What did the study find?
The researchers report that the wearing of mass reduces the transmission of COVID-19 by 40%.
The rate of global mask use is currently 59.0%, and if this rate were increased to 95% through mandates, the number of COVID-related deaths would fall by 0.82 million by January 21st, 2021.
The rate of mask use ranged from 41.9% in North Africa and the Middle East to 79.2% in Latin America and the Caribbean.
The beneficial effect of universal mask-wearing would be most significant in countries such as India (where it would prevent 158,832 deaths), the United States (would prevent 93,495 deaths), and Russia (would prevent 68,531 deaths).
“The benefits of increased mask use are greatest in settings with substantial ongoing transmission and low current levels of mask use regardless of sociodemographic status,” say the authors. “This low-cost intervention that is available and accessible to all populations, regardless of socio-economic status or other dimensions of inequity, has enormous health benefits and might also lead to large economic benefits by delaying the need for re-imposition of social distancing mandates.”
One of the best mitigation strategies available
The team says more COVID-related deaths are expected in the second half of 2020 than occurred in the first six months of the year.
As well as large epidemics unfolding in Latin America, the Middle-East, and South Asia, seasonality suggests a second wave can be expected in the Northern Hemisphere, say Gakidou and colleagues.
“Ensuring that individuals, as well as, local, national and global decision-makers are all doing everything in their power to achieve the highest rates of mask use in all exposed populations is one of the best strategies available to us to mitigate the toll of the pandemic in the months to come,” they conclude.
*Important Notice
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.